Engine Need tuning help!


Jul 31, 2023
A couple of months ago I bought a 1993 5.0 LX convertible. There has been a lot done to the car but in my opinion it’s sluggish. I need to figure out how to make it all work together. It has a 65mm throttle body, 77mm mass air meter, the computer has a chip, it has roller rockers, E303 cam, headers, SVO aluminum heads, GT 40 Lightning intake, 3.73 gears, and a Baumann shift kit. I think I got everything. I had a buddy check the timing and he advanced it but thought it could be a tooth off because it didn’t help performance. It runs great and idles smoothly it just lacks power. ANY suggestions are welcome!
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Those specs sound similar to the 93 I sold not long ago. It had 4.11 rear though and even with that it wasnt putting much to the pavement. If your engine is not a stroker than you probably have either 302 or if its punched maybe 306 displacement. Its just not going to be a powerhouse. The AOD probably robs at least 50hp before anything else gets the the rear tires.

Mine felt really nice in moderate driving conditions. It made you think like, if it feels this good at 1/2 throttle then it should really take off if you floor it. But, it just didnt.

With your setup and the AOD trans I doubt you will ever even hit 250hp at the rear wheels. You just cant expect too much from it in my opinion, at least in raw acceleration that is.
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With a chip most tuners want the base timing at 10 degrees so advancing it will actually hurt performance.

Have you tried to pull codes? What injectors are in it? What size exhaust? Have you verified the rear gear ratio?